Communication between devices as well as between a device and a data centre will dominate in the future communication network. Cheaper storage technology makes it possible for people and devices to obtain massive amounts of information. With the development of the processing power of a chip and real-time online technology, the device will be a major participant in the future mobile communication. Machine to machine communication is a general term of techniques and combination thereof for realizing data communication and exchange between machines, as well as between machines and people by applying the communication technology.
The MTC technology integrates the communication technology and the information technology and can be applied to the bidirectional communication such as remotely collecting information, setting up parameters and sending instructions. Thus, different application schemes can be implemented, for example, safety monitoring, automatic selling, goods tracking and so on. Accordingly, almost all devices involved in the daily life are likely to be potential service objects.
In the MTC system, entities participated in communication include a large number of MTC devices and MTC applications. In order to reduce network load and save network resource, it needs to optimize the management of the MTC devices and MTC applications in groups. As such, the MTC device and MTC applications can be controlled, managed, billed and so on in groups, so as to adapt to requirements of the operators. After grouping the MTC devices and MTC applications, it is needed to secure the communication between the devices in a group and the network, as well as between the network and the groups. Specifically, on the one hand, it needs to secure the communication based on groups because the communication based on the MTC group can reduce the network resource load. On the other hand, a single MTC device or MTC application in an MTC group may need to communicate with the network separately, which requires to secure the communication of the single MTC device or MTC application.
At present, separate and different security solutions are provided for communication based on the MTC group and communication of a single MTC device or single MTC application in the MTC group. For MTC devices/MTC applications in one MTC group, in order to secure the communication based on the MTC group and communication based on a single MTC device/MTC application, the MTC device/MTC application is required to simultaneously have a security key of communication based on the MTC group and a security key of communication based on an MTC device/MTC application. However, such two security keys for different purposes are obtained in different security processes, resulting in increase in the signalling load of the MTC communication system. Therefore, for the scenario of communication based on the MTC group, how to simultaneously obtain two types of session keys in one key negotiation process is a technical problem urgent to be solved.